The development of speech in the child is the process by which he learns to make use of the language of the persons among whom he is reared. From the moment the infant utters his first cry at birth, he vocalizes during most of his waking hours, producing very early all the sound units which later form his language and doubtless most of the sound units of all spoken languages. Blanton1 noted that during the first thirty days of life six consonants—m, n, g, h, w and r—and several vowel sounds—o, e, oo and a—were uttered by the infants whom she observed.
These sounds, however, are mere babblings, the result of the instinctive activity of the organism. The onset of speech dates from the time at which the child begins to use the sounds combined into words, purposively, in order to make known his wants and to express
KARLIN IW, KENNEDY L. DELAY IN THE DEVELOPMENT OF SPEECH. Am J Dis Child. 1936;51(5):1138-1149. doi:10.1001/archpedi.1936.01970170134012